The use of inhalation devices in the administration of medicaments, for example in bronchodilation therapy is well known. Such devices generally comprise a body or housing within which a medicament carrier is located. Known inhalation devices include those in which the medicament carrier is a blister strip containing a number of discrete doses of powdered medicament. Such devices usually contain a mechanism of accessing these doses, usually comprising either piercing means or means to peel a lid sheet away from a base sheet. The powdered medicament can then be accessed and inhaled. Such a mechanism may also be used for dispensing medicament in tablet form wherein peeling away the lid sheet from the base sheet reveals a tablet for removal and subsequent consumption.
With such devices access to each dose is typically enabled on a serial basis by advancing the strip within the device to sequentially bring each discrete dose of medicament carried by the strip to an opening station. Known devices, including that sold under the trademark DISKUS® by GlaxoSmithKline Plc, typically comprise a user-actuable lever mechanism coupled to a strip advancement mechanism (e.g. via a gear train). Thus, the user actuates the lever to advance the strip thereby causing the next discrete dose of medicament to be made available at the opening station.
Such devices also typically comprise a mouthpiece through which a user inhales to achieve inhaled delivery of the discrete medicament dose. It is desirable that a protective cover is provided to the mouthpiece to prevent contamination by dirt or dust particles. In use, the mouthpiece cover is removed by the user to reveal the mouthpiece before inhaling therethrough. Certain devices, including the DISKUS® inhalation device of GlaxoSmithKline Plc, have a mouthpiece cover that is attached to a housing of the device and reversibly movable (e.g. by pivotal movement) from a position, in which the mouthpiece is covered to one in which the mouthpiece is uncovered.
The Applicant has appreciated that it is potentially desirable from the standpoint of minimizing the number of steps required to ready the device for action to couple the movement of the mouthpiece cover to reveal the mouthpiece with actuation of the lever to advance the strip within the device. The Applicant has however, also appreciated a potential problem in that the user may desire to open the cover to reveal the mouthpiece for cleaning etc. but not wish by that action to also result in advancement of the dose. In solution to this problem, Applicant has now devised a device having a movable mouthpiece cover that is sequentially movable from a first ‘mouthpiece covered’ position to an intermediate ‘mouthpiece uncovered’ position, but then further movable to engage a strip advancement mechanism to cause advancement of the strip within the device.